The first time I was in grad school I lived in an apartment with a couple other guys: we cooked our own meals and they were away every weekend.

One weekend I decided to fix an Olde Familye Favoritee: creamed tuna over mashed potatoes.

No problem with the mashed potatoes. I called the lady I later married to ask how to fix a cream sauce (milk, butter, and flour). I never thought to ask about the canned tuna and learned after afterwards that you really, really should drain off the oil it's packed in BEFORE adding it to anything.

Well, it WAS edible. And it gave rise to my Law Of Cooking: Nontoxic in, nontoxic out (that is, you can eat it but you might want to think twice about doing so).